230 EEV. J. P. BLAKE ON THE 



is somewliat similar to M. De Loriol's C. Lamherti^ but differs in 

 details. 



In tlie Swindon Sands, west of Swindon. 



Ttjebo roucAKDi, De Loriol. PI. IX. figs. 6, 6a. 



The English specimens which I refer to this species have 

 flattish whorls and well-marked sutures. The upper sloping part of 

 the whorls has three granular longitudinal lines, the upper one 

 having the largest granules ; these are followed below by two 

 strong granular ridges on the same level, with a concavity trans- 

 versely striated between, this concavity forming the suture of the 

 earlier whorls. The base has concentric granulose lines of unequal 

 strength. It is imperforate and has a twisted columella. De 

 Loriol states that his species has sometimes two rows of granules at 

 the edge, in which case there is little difference. 



Eather common in the Swindon Sands, west of Swindon. 



TuEBO APEETTJS, spec. uov. PL IX. fig. 7. 



This is only known as a cast. The spire is low, apical angle 

 about 95° ; whorls two, probably subquadrate and bicarinated, the 

 upper keel the stronger. The aperture was greatly expanded ; and 

 the umbilicus was open. It seems worth while to name this, as it 

 is rather common in the Roaph ; but at present it can scarcely be 

 said to be known. I have seen no figures of foreign species of 

 which this could be the cast. 



EissoA ACUTiCAEnfA, spcc. uov. PI. IX. fig. 4. 



Apical angle 27° ; whorls turreted, with a sharp keel, which is 

 ornamented by fine transverse widely spaced lines. The last keel is 

 thus divided into low knobs ; and there are longitudinal lines on the 

 base of the whorl. Length 2 lines. This is nearly allied to the 

 R. unicarina of Buvignier ; but the keel is so much sharper as to 

 completely alter the shape of the whorl. 



Eather common in the creamy limestones of Bucks. 



Theacia teneea, Agassiz. 



This name is used to denote a much broader shell than our 

 ordinary T. depressa. The two species are frequently united by 

 authors ; but there do exist two perfectly distinct ones, and the Port- 

 land forms agree very well with Agassiz's figures, as do those of 

 Boulogne. 



COEBIJLA SALTANS, SpeC. UOV. PL IX. fig. 9. 



Minute, length -J- the breadth, valves very nearly equal, beaks 

 nearly median, anterior side elliptically rounded ; posterior side 

 obliquely truncated, the hinge-margin remaining nearly parallel to 

 the pallial border for some distance, and there being a fiat area sepa- 

 rated by a line which is concave towards the pallial border. This 

 gives the shell a humpbacked appearance. 



It is nearly allied to C. fallax and C. dammariensis ; but neither 

 of these has the shoulder-like posterior side. 



